Make your own spray paint cans

[Mikeasaurus] found a way to build his own refillable spraypaint canister. The donor vessel used here is a plastic soda bottle. It’s a great choice since it is engineered to house a pressurized liquid and you can find them for free by intercepting a satisfied soda consumer before they reach the recycling bin.

He repurposed the spray nozzle from a commercial spray paint can. By first releasing all of the pressure from the empty paint he could then use a hack saw to remove the top disk. He used Sugru to attach it to the bottle cap which has a hole drilled in the center to accept the feed straw. We wonder if there wouldn’t be a better way to attach this from the inside of the cap for better resistance to bottle pressure?

The final piece of hardware is a Shrader valve from a bicycle inner tube. This lets you pump up the pressure in the bottle. You’ll need to dilute the paint you use to make it sprayer-friendly. [Mikeasaurus] diluted his six to one which might have been a bit too much judging from the drips seen in the video after the break.

I’ve wondered why there were no reusable aerosol cans in the first place. All it would take is a can with a threaded base. Turn the empty can upside down and fill it with whatever you felt the need to atomize and spray into the air. Load it and a base into a machine that vacuums out all of the air and then pressurizes the can with the propellant charge before screwing the base down tight. Evacuate extra propellant back to the holding container and replace with atmosphere. Release the can.

Spray to your heart’s delight and when the can is “empty”, just put it back in the machine which will unscrew the base and evacuate any remaining propellant, replace with atmosphere and release the once again opened aerosol can for you to do whatever you want with the contents.

Would be a lot more durable than a bicycle schrader valve on a soda bottle.

The spray nozzle assemblies can be threaded into the cans too for replacement of use of different sized ports and sprayer attachments.

What is the propellant used in commercial production rattle cans these days? I never investigated what the industry went with after CFCs were verbotten. The reusable cans I’m imagining could be of a large enough gauge steel that compressed atmosphere, or at least refined nitrogen gas, could be used.

harborfreight has them from time to time, sears carries them, graingers carries them. I think they are in half of my industrial supply catalogs. Pretty common actually. There are cheaper ones, but the millwalkee sprayer brand, sure shot, are the best Ive used.

If you don’t have an air compressor, then search Internet for airbrush propellant

Like the subject project and most people that visit HaD, I would spend an insane amount of time trying to make something myself before buying an expensive commercial product. Hopefully unlike most, my attempts end up looking and working like an aborted Chuckie doll so I end up buying the commercial product anyway.

Like the spirit of DIY’ers and HaD’ers everywhere, even though many of my project attempts fail, I still keep trying again and again. (most people call that stupid but I’m sure HaD readers understand the hacker spirit).

Wow, that’s really not good performance for spray painting. A “sprayer” needs to “spray” a mist (thus the word “spray” in the name of spray paint.) This is pumping out a low pressure stream that doesn’t even atomize.

Now, if you like the runny paint look that says “I paint on walls because I think you should care, but I don’t care at all, therefore you won’t either, but because I’m too into myself to notice I’ll do it anyway”, that’s one thing, but then call it a paint squirt gun, not sprayer. Like someone else said, a super-soaker would do that just as well.

A hack should be functional, and this one doesn’t even function. Now, if he filled it with water, it’d be an awesome air-powered squirt gun, and I’d approve of that.

I have a store bought reusable spray can,
I fill it with rubbing alcohol to clean metal,
sometimes other cleaners, you pressurize it
with an air compressor, cost was around $10
to $20, BTW the pressurized air lasts a very
short time compared to a real spray paint can,
you need to re-pressurize often.

It’s not pure oxygen, but just atmospheric air (which is mostly nitrogen). Good luck getting it to autoignite at any pressure that is attained using a common household compressor without also using a substantial source of heat or an intentional ignition point.

If I were using such a thing (and I will be soon, now that I know it exists) I’d worry more about the cloud of atomized fuel emanating from the business end of the sprayer finding an ignition source than anything else.

And “worrying more” is still not worrying all that much much: I’ve been known to clean stuff using aerosol cans of ether, toulene, and various other fun stuff. No big deal.

I mean, FFS: WD-40 is mostly kerosene, and people seem to handle that OK without bursting into flames. Common hairspray often uses propane as a propellent. Etc, so on, so forth. *shrug*

Am I the only one that thought this looked like bong for crack at first glance?

It’s a good idea, though, I never would have thought of trying to make refillable spray paint.

However, I think a good way to make the spray valve attach from the inside would be to cut away the edges of the can top until it could fit inside of the bottle cap. Cut a hole in the middle of the cap for the nozzle, epoxy the metal to the cap from the inside, then epoxy the cap down onto the bottle.

I remember making grenades for paintball in a similar fashion using a bottle and a bike valve to pressurize them. a ball bearing in a section of tubing folded over and held in place with a rubber band was a sort of “impact fuse” that didn’t always work the way you wanted it to. in the end we would buy the tippmann grenades and just use those. but it was an interesting project.